Wild edible mushrooms are valuable non-wood forest products with ecological, cultural and economic relevance, but their integration into forest resource assessment and planning is constrained by scarce large-scale productivity data. We developed a spatially explicit, expert-based framework to estimate and map the potential harvestable productivity of socio-economically important edible mushroom taxa under favourable fruiting conditions. Using Aragón, Spain, as a case study, we modelled 15 target taxa in Spanish Forest Map units characterized by habitat class, stand structure, edaphic substrate, and topography. In two independent elicitation sessions, 30 experienced mushroom pickers estimated habitat-specific productivity, harvesting-effort parameters and taxon-specific correction coefficients. These estimates were converted into annualized estimates of potential harvestable productivity using taxon-specific peak-week production fractions informed by historical production patterns. The model revealed strong taxon–habitat differentiation and spatial heterogeneity, with the highest values concentrated in Pyrenean forests and the Iberian System. Model-estimated regional potential harvestable production under favourable conditions was 15,940 t·yr⁻¹; Lactarius group deliciosus (42.2%), Morchella sp. (17.4%) and the Boletus edulis commercial group (12.2%) jointly accounted for 71.8%, while all remaining taxa accounted for 28.2%. The framework provides an operational approach for mapping the potential harvestable productivity of wild mushrooms in data-limited regions and supporting forest resource assessment, multifunctional forest planning, sustainable harvesting, and mycotourism.
Preservation and management of existing, as well as the establishment of new forests, can significantly alleviate the negative impacts of global warming. Seedling production is currently reliant on the use of synthetic fertilizers that are detrimental to the environment. In nature, the development, growth, and resilience of plants to abiotic and biotic stress are modulated by rhizosphere microbial communities. We hypothesized that beneficial plant-growth promoting (PGP) bacteria isolated from the sessile oak (Quercus petraea (Matt.) Liebl.) rhizosphere and applied during sessile oak seedling production would improve seedling growth and quality. We obtained bacterial isolates from the sessile oak rhizosphere able to solubilize phosphates and produce indole-3-acetic acid, siderophores, and 1-aminocyclopropane-1-carboxylate deaminase. Five bacterial strains with multiple PGP activities, applied individually or as consortia, improved the growth and overall quality of sessile oak seedlings in the nursery under semi-controlled conditions, as evident from the morphological growth parameters and a comprehensive estimate of plant quality based on sturdiness quotient and Dickson’s quality index. The five-member consortium stood out as the most promising candidate for the production of high-quality sessile oak seedlings. The proposed strategy for an ecologically- and environmentally-friendly production of sessile oak seedlings could be implemented in sustainable forest management practices upon further investigation of the consortium efficacy under complex and unpredictable field conditions.
Riparian forests are among the most diverse ecosystems, yet their diversity is threatened by hydrological alterations. This study examines patterns of vascular plant diversity and structural characteristics across riparian forests in the Irati Basin, a transition zone between temperate and Mediterranean climates in northern Spain that includes a river section affected by a dam. Furthermore, it identifies the main environmental and structural drivers shaping this diversity. We sampled the composition of vascular plants and the structure of 54 forest plots and calculated their taxonomic, functional and phylogenetic diversity. We compared diversity indices and environmental and structural variables among two control sections (temperate and Mediterranean) and the dam-affected Mediterranean section. A total of 424 species were recorded across the study with an exceptional mean richness of 76.7 species per 200 m2. Plots in the temperate section consistently showed higher diversity and were located at higher elevations, with cooler temperatures, higher rainfall and significantly greater bryophyte cover. The Mediterranean sections (control and dam-affected) were more similar to each other, although the dam-affected section exhibited greater summer river flow, soil organic matter and electrical conductivity, as well as higher volumes of terminal and dead trees, likely associated with the high abundance of beavers in this section. Additionally, the dam-affected plots hosted wet-habitat taxa missing in the control sections. These differences in the dam-affected section, particularly in summer river flow and the occurrence of wet-habitat taxa, are consistent with patterns that may reflect hydrological regulation, although alternative environmental and spatial factors cannot be excluded. Environmental and structural variables influenced overall diversity patterns, with each of the analysed diversity dimensions responding to different drivers, although the increase in mean annual temperature negatively influenced most of them. Overall, our findings highlight the need to consider multiple diversity dimensions and environmental drivers when assessing patterns of riparian forest diversity to fully understand ecosystem complexity and therefore effectively manage and conserve riparian ecosystems.
The timing of budburst is a key determinant of a tree’s fitness within its environment. While numerous studies have investigated the environmental drivers of phenology, less attention has been paid to how phenological traits influence individual tree performance within the forest. Here, we assessed at the individual-tree scale whether earlier budburst is associated with enhanced growth and how intra-annual growth dynamics differ between early- and late-flushing trees. We analyzed annual and intra-annual growth together with budburst phenology across the Spanish plots of the ICP Forests intensive monitoring network (Level II) representative of major forest ecosystems in Spain, which include Mediterranean and temperate forests. Annual growth data were obtained from 296 trees monitored over 28 years, while phenological observations covered 13 years and intra-annual growth 11 years for a subset of 127 trees. On average, trees with earlier budburst exhibited higher annual growth, and the relationship was positive in seven of the nine species, although it was individually significant only in Pinus sylvestris and P. pinaster, and the differences among species were not statistically conclusive. No significant relationship was found in P. halepensis, P. pinea, P. nigra, Quercus ilex, Q. suber, Q. petraea, or Fagus sylvatica; in F. sylvatica the tendency was negative, possibly owing to its high sensitivity to late frosts. Neither leaf habit nor any single climatic or edaphic variable significantly modified the relationship, although the plots of the two species with a significant relationship all belonged to the group of cooler sites, and none of the species from the warmer and drier sites showed it. The seasonal course of growth differed between early- and late-flushing trees: the higher growth of early-flushing trees was not restricted to the onset of the growing season but extended over the whole growth period.
Populus tremula (Eurasian quaking aspen) is one of the most widespread dioecious tree species in the Northern Hemisphere, yet large-scale geographical patterns of sex distribution remain poorly understood. We surveyed 456 flowering stands across 44 populations at the southwestern rear-edge of the species’ natural range in the Spanish Central Range (central Spain), analysing sex distribution in relation to climatic, topographic and anthropogenic variables. Stand area was measured in 432 stands and foliar flushing phenology in 90 stands. Male stands strongly predominated (3.8:1), but this bias was highly structured geographically. Across the approximately 80,000 ha of the Adaja and Arevalillo basins included in the study area, virtually all flowering stands were male, representing, to our knowledge, the most extensive geographical segregation yet documented in a natural population of a dioecious forest tree. Annual precipitation was the environmental variable most strongly associated with sex distribution, with females becoming progressively more frequent towards wetter environments. Female stands occupied significantly larger areas than male stands, whereas males flushed significantly earlier in spring. We propose that this remarkable spatial pattern is best interpreted as the cumulative outcome of long-term ecological, demographic and historical processes. Persistent water limitation probably promoted the progressive loss of female clones, whereas limited sexual recruitment, reinforced by centuries of landscape transformation, restricted the replacement of locally extinct female genotypes. The resulting scarcity of female stands may severely constrain sexual recruitment, limiting genetic diversity and reducing the long-term adaptive capacity of these rear-edge populations under ongoing climate change.
